President Barack Obama is warning the world and America about a rising populism that he says is sweeping the planet, urging people to be vigilant about the future.
“We are going to have to guard against a rise in a crude sort of nationalism or ethnic identity or tribalism that is built around an ‘us’ and a ‘them,’” Obama said during a press conference in Greece.

He referred to World War I and World War II as the consequence of a rising sense of nationalism in Europe.